1. Field
The present disclosure relates to a fuel cell stack.
2. Description of the Related Art
For example, a solid polymer electrolyte fuel cell includes a membrane electrode assembly (MEA), in which an anode electrode is disposed on one surface of an electrolyte membrane (solid polymer ion-exchange membrane) and a cathode electrode is disposed on the other surface of the electrolyte membrane. The MEA and a pair of separators, sandwiching the MEA, constitute a power generation cell (unit cell). Typically, a predetermined number of such power generation cells are stacked and used, for example, as a vehicle fuel cell stack, which is mounted in a fuel cell vehicle (fuel cell electric automobile or the like).
Fuel cell stacks include a fuel gas channel, an oxidant gas channel, and a coolant channel. The fuel gas channel, for supplying a fuel gas to the anode electrode, and the oxidant gas channel, for supplying an oxidant gas to the cathode electrode, are formed along surfaces of the separators. The coolant channel, through which a coolant flows, is formed between separators of adjacent power generation cells so as to extend along surfaces of the separators.
Some fuel cell stacks, which are called “internal manifold fuel cell stacks”, further include a fuel gas manifold, through which a fuel gas flows; an oxidant gas manifold, through which an oxidant gas flows; and a coolant manifold, through which a coolant flows. These manifolds extend through the fuel cell stack in the stacking direction. The fuel gas manifold (fluid manifold) includes a fuel gas supply manifold and a fuel gas discharge manifold, and the oxidant gas manifold (fluid manifold) includes an oxidant gas supply manifold and an oxidant gas discharge manifold. The coolant manifold (fluid manifold) includes a coolant supply manifold and a coolant discharge manifold.
In the fuel cell stack, fluid manifold members, each of which is connected to a corresponding one of the fluid manifolds, is disposed on at least one of end plates. A fluid, which is a fuel gas, an oxidant gas, or a coolant, is supplied to or discharged from the fuel cell stack through the fluid manifold member. For example, Japanese Unexamined Patent Application Publication No. 2009-224195 describes a fuel cell stack in which a resin manifold member is disposed on one of end plates, and the resin manifold member has a reinforcement portion that is held by the one of the end plates.
Japanese Unexamined Patent Application Publication No. 2015-60716 describes a fuel cell stack in which a fluid manifold member has a rubber body. A rubber flange, which is integrally formed with the rubber body, is disposed at a joint portion where the rubber body is joined to an end plate. The rubber flange is pressed against and held by the end plate by using a metal bracket that is fixed to the end plate.